That corrosive-primed ammo will still go bang for a long time after anybody reading this post will still be able to pull a trigger. If the sealed crate/tin is undamaged and you store it in moderate conditions it will be GTG. I am still shooting 8mm Turk that was made before WWII (dated 1937). I average 1% - 2% failure rate with that stuff.
Non-corrosive primed ammo will last just as long if you avoid extremes during storage.
On the other hand, I have seen some 50s dated corrosive Equadorean 8mm in which one lot would shoot fine and another would be a 90% failure to fire but I suspect that had more to due with the manufacture of the ammo and not the age.